The following background discussion is not an admission that anything discussed below is citable as prior art or common general knowledge.
U.S. Pat. No. 4,420,180 describes a floor mat comprising a main portion for lying flat on an automobile floor and an upwardly inclined portion for lying on an inclined surface within the automobile, such as behind the pedals. The main portion includes a centrally disposed downwardly recessed area forming a pan having a floor and surrounding sides for catching fluid. A plurality of ridges, having a triangular cross-section, rise vertically from the floor of the pan for holding pants and the like above fluids caught in the pan. The forwardly extending portion includes ribs which extend in the longitudinal direction of the mat for channeling fluids backward into the pan. Additional ribs are formed on the forward portion which are inclined downwardly and inwardly for channeling fluid away from the edges of the mat toward the center of the mat.
U.S. Pat. No. 5,482,759 describes an automobile floor mat having a removable and reversible pan portion that snugly fits inside a central recessed area to collect contaminants. One side of the pan is provided with a plurality of diagonal ridges, the space between the ridges forming grooves to collect liquids. The other side of the pan may be constituted of an abrasive surface of the sand paper type.